A pinboard by
Urbi Chatterjee

PhD Scholar, Indian Institute of Technology Kharagpur


A protocol to provide proofs of sensor data using unreliability of Physically Unclonable Functions

The Internet of Things (IoT) is envisaged to consist of billions of connected devices. These devices are often coupled with sensors which generate huge volumes of data enabling control-and-command in the IoT paradigm. However, integrity of this data is of utmost concern for securing the IoT, and is promisingly addressed leveraging the inherent unreliability of Physically Unclonable Functions (PUFs) w.r.t. ambient parameter variations, using the concept of Virtual Proofs (VPs). These proto- cols do not use explicit keys and aim at proving the authenticity of the sensor information from alterations by adversaries. However, a key observation is that the existing protocols do not use the sensor data as the challenge of the PUFs. The resultant protocols have often a often allow only a limited number of authentication attempts, and require linear search in the verifier database rendering them unsuitable for IoTs. To alleviate these issues we develop a new class of protocols here the sensor data is used as a part of the challenge space. This approach brings forth several challenges related to the application of the sensor data in the PUF to ensure that changes in the sensor values have a high sensitivity on the overall PUF response. We illustrate through actual experiments with FPGA PUFs designed using the Double Arbiter PUF (DAPUF) architecture which are implemented with superior uniformity, uniqueness, and reliability on Xilinx Artix-7 FPGAs. Without loss of generality, we develop the protocol to authenticate sensor data against temperature variation. In the security analysis, we have shown that how the unreliability of the responses across the temperature variation can be utilized to prove the trustworthiness of the sensed data. We show that the protocol on such PUF designs can be effectively used to authenticate wide variations of temperature from -20 ◦ C to 80 ◦ C.